The wild card entry from Italy converted three of his eight break point chances to prevail after one hour and 15 minutes.
"It's unbelievable. I didn't feel so well in the beginning and he was playing very good, very aggressive".More news: Bolivia Clashes: Third Person Killed in Disputed Election
Alex de Minaur and home favourite Jannik Sinner will meet to decide this year's champion at the Next Gen ATP Finals after respective semi-final triumphs over Frances Tiafoe and Miomir Kecmanovic.
Top-seeded Alex de Minaur of Australia, who was runner-up previous year, leads Group A after defeating Miomir Kecmanovic of Serbia 4-1, 4-3 (4) 1-4, 4-0 to make it two wins out of two.
"I think the crowd gives you an energy which is very important for a player", Sinner said. He sealed the victory on his first match point when his American opponent hit a forehand into the net. "In the same manner, you've got to remember that you're opponents", said De Minaur, who finished runner-up to Stefanos Tsitsipas previous year at the Next Gen ATP Finals. De Minaur said: "Here you put everything aside".More news: Brazilian judge orders release of ex-president
Tiafoe went on a five-game streak from 2-1 down in the first set against the Swede at Allianz Cloud and never looked back. It's easy because you know that no matter what happens on the court, you're still going to be the best of friends. "In the same manner, you've got to remember that you're opponents". "It's hard, but easier in some ways (playing a friend)", De Minaur said. This is expected to be a tough match for Jannik Sinner as he is playing against the top seed. "I'll just try my best". "It's about whoever plays better on the day".
He made the final in 2018, only to lose to current World No. 6, Stefanos Tsitsipas.More news: Mercury to make rare transit of the sun on Monday